概括
羊球蛋白基因测序揭示了胎儿,成人前和成人形式之间的高同质性. 内子中的独特插入表明最近的分歧和转子子样元素,玛基因具有胎儿特异性的作用.
科学领域:
- 基因组学就是基因组学.
- 分子生物学分子生物学
- 进化生物学 进化生物学
背景情况:
- 全球蛋白基因对氧气运输至关重要,并表现出发育阶段特定的表达.
- 了解全球蛋白基因进化为遗传调节和物种化提供了洞察力.
研究的目的:
- 确定山羊胎儿 (玛),预成年 (β C) 和成年 (β A) 全球蛋白基因的完整核酸序列.
- 分析这些山羊球蛋白基因之间的进化关系和结构差异.
主要方法:
- 完整的核酸测序山羊的玛蛋白,β-C和β-A球蛋白基因.
- 用山羊球蛋白伪基因 (psi beta X,psi beta Z) 进行比较序列分析.
主要成果:
- 羊胎儿,预成年和成年球蛋白基因在编码和非编码区域显示出高同质性 (~90%).
- 主要的差异归因于大型内子的插入:玛 (247 bp),βA (318 bp) 和βC (252 bp插入,60 bp删除).
- 羊的玛基因在胎儿阶段特别起作用,与人类胎儿球蛋白基因不同.
结论:
- 最近,山羊的玛,βA和βC球蛋白基因发生了分离.
- 涉及祖先伪基因功能基因对的基因重复事件可能形成了psi beta X-beta C和psi beta Z-beta A.
- 内部插入表现出类似转子子的特征,并在山羊基因组中广泛存在.
相关概念视频
Transgenic Organisms
Overview
Transcription Factors
Tissue-specific transcription factors contribute to diverse cellular functions in mammals. For example, the gene for beta globin, a major component of hemoglobin, is present in all cells of the body. However, it is only expressed in red blood cells because the transcription factors that can bind to the promoter sequences of the beta globin gene are only expressed in these cells. Tissue-specific transcription factors also ensure that mutations in these factors may impair only the function of...
Gene Families
Gene families consist of groups of genes proposed to have originated from a common ancestor. Typically these arise through events in which a gene or genes are mistakenly duplicated during cell division. Unlike their parent genes (which are subject to selection pressure to maintain function), these gene copies do not need to preserve their sequences and may evolve at a relatively faster rate.
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
Protein Families
Protein families are groups of homologous proteins; that is, they have similarities in amino acid sequences and three-dimensional structures. Protein families usually occur because of gene duplication, where an additional copy of a gene is inserted into the genome of an organism. Mutations that change the amino acids but still allow the protein to be properly synthesized, will lead to new protein family members. If these new proteins contain similar amino acids in key locations, protein...
Gene Duplication and Divergence
The seminal work of Ohno in 1970 popularized the idea of gene duplication and divergence. DNA sequence comparison studies reveal that a large portion of the genes in bacteria, archaebacteria, and eukaryotes was generated by gene duplication and divergence, indicating its critical role in evolution.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
General Transcription Factors
Tissue-specific transcription factors contribute to diverse cellular functions in mammals. For example, the gene for beta globin, a major component of hemoglobin, is present in all cells of the body. However, it is only expressed in red blood cells because the transcription factors that can bind to the promoter sequences of the beta globin gene are only expressed in these cells. Tissue-specific transcription factors also ensure that mutations in these factors may impair only the function of...


